course PHY202
I have a question about Problem 12 it says: When a gas is taken from a to c (on the graph) along the curved path, the work done by the gas is W= -35J and the heat added to the gas is Q= -63J. Along path abc, the work done is W= -48J. a)What is Q for path abc? b) If Pc=1/2Pb, what is W for path cda? c)What is Q for path cda? d) What is Ua - Uc? e) If Ud - Uc = 5 J, what is Q for path da?
I have a question about Problem 12 it says: When a gas is taken from a to c (on the graph) along the curved path, the work done by the gas is W= -35J and the heat added to the gas is Q= -63J. Along path abc, the work done is W= -48J. a)What is Q for path abc? b) If Pc=1/2Pb, what is W for path cda? c)What is Q for path cda? d) What is Ua - Uc? e) If Ud - Uc = 5 J, what is Q for path da? Please help me get started on this one. THa
This comes down to good old energy conservation.
When energy is put into a gas, it goes into internal energy and work. So if `dQ is the thermal energy that goes into a system, `dW is the work done by the system and `dU is the change in the internal energy of the system, we have
`dQ = `dW + `dU.
Keeping this in mind, try to answer the following questions:
1. From the information given about the curved path ac, what is the change in the internal energy of the gas?
2. Path abc also goes from state a to state c. So the change in internal energy is the same as along the curved path. So how much does the internal energy of the system change along abc, how much work is done along that path, and how much thermal energy therefore goes into the system?
3. How does the area beneath the path cd compare to the area beneath the path ab? What does this have to do with the comparison between the work done along ab and the work done along cd?